DIY mapping

[jevvy]

Been pondering over the weekend(always dangerous) and was wondering what software mappers use to re-map an ECU.

 

My guess is that they take a number of outputs from the engine (temperature etc) and use this info + the results from a dyno to make tweaks to the 3D maps that our ECU's use to control the ignition/fuel etc

 

I know you can go with an after market system that allows you to have all this control but it strikes me that with the right software and interface this control is already there....?

 

Also can this all be done without a Dyno - surely it must be possible to work out power with an idea of the cars weight, gear ratios, a timer and accurate RPM readout and some maths. If this is the case and you can get yr lappy plugged into the ECU it must be possible to tune the car on the road.

 

I know there is a lot to read an understand about mapping engines and that untold damage can be done if you push things too far but I'd love to know if DIY mapping is possible without big investment in after market systems and replacement sensors.

 

I have pretty much decided that I'm going to take my car to Wayne/9M but like shop alignment I hate the thought of paying someone to do something that if a change is made you need to pay them again to do it all again. If my £450 mapping charge gets me 1/2 way to a DIY mapping setup then its almost a consideration.

[Northy]

My mate works for Super Chips and they regularly map cars on road tests and the dyno - apparently it helps set up the driveability.

 

I seem to remember seeing something on DDK about mapping yourself - but I don't think that was for stock ECU's. It can't be that hard to do once you have the software.

[jevvy]

It can't be that hard to do once you have the software.

 

Thats what I'm thinking - as long as you have a way to record changes in performance and you dont "tune it to the moon" then it should be good fun.

[Northy]

I bet you can download the software on something like Limewire... might be worth a dig around. Sadly this is no use to me and my SC...

[Tim]

I am the poster mostly responsible for Megasquirt/ EFI postings on DDK and when I put my car back on the road will go back OTR with a full EFI setup. It is a 2.4 911T and will be using Triumph motorbike throttle bodies and a Ford EDIS crankfired ignition system. The ECU will be a Megasquirt unit ( but could have easily been a DTA or Emerald or other ) I choose Megasquirt as I've used it before, quite sucessfully and a Maserati Biturbo. The Maserati I tuned on the road, laptop in hand. Went from undriveable to fantastic in about 1 Hr. It would have benefitted from a wideband O2 sensor, especially being a Turbo, but they were expensive at the time. I am quite confident that tuning on the road will get me very satisfactory results. Refinement in driveability will come over time as I hone the settings to suit weather and driving conditions.

My setup is not exactly standard, but the principals have to be the same. The problem that I feel you will get is the lack of available information about the OEM ECU. I cannot talk about that part of the system, only suggest that a DIY re-map is quite possible. Third party and especially Megasquirt, a complete open source ECU project, make the tools and information available to allow the user to re-map. The end result will be dependant upon the time and skill of the re-mapper. VERY EXPENSIVE engine damage can result from mapping mistakes so take care !

I'll let you know how I get on

Tim

[jevvy]

must be my first ever wrong room - considered it banter more than a technical thang

 

I am the poster mostly responsible for Megasquirt/ EFI postings on DDK and when I put my car back on the road will go back OTR with a full EFI setup. It is a 2.4 911T and will be using Triumph motorbike throttle bodies and a Ford EDIS crankfired ignition system. The ECU will be a Megasquirt unit ( but could have easily been a DTA or Emerald or other ) I choose Megasquirt as I've used it before, quite sucessfully and a Maserati Biturbo. The Maserati I tuned on the road, laptop in hand. Went from undriveable to fantastic in about 1 Hr. It would have benefitted from a wideband O2 sensor, especially being a Turbo, but they were expensive at the time. I am quite confident that tuning on the road will get me very satisfactory results. Refinement in driveability will come over time as I hone the settings to suit weather and driving conditions.

My setup is not exactly standard, but the principals have to be the same. The problem that I feel you will get is the lack of available information about the OEM ECU. I cannot talk about that part of the system, only suggest that a DIY re-map is quite possible. Third party and especially Megasquirt, a complete open source ECU project, make the tools and information available to allow the user to re-map. The end result will be dependant upon the time and skill of the re-mapper. VERY EXPENSIVE engine damage can result from mapping mistakes so take care !

I'll let you know how I get on

Tim

 

Thanks Tim, sounds like you have had some canny projects.

 

Your comments have certainly helped me realise its possible with aftermarket stuff but what I really want to find out is if this can be bypassed so I can map my current ECU whilst on the road like Wayne/9M do on a dyno.

 

I fully appreciate the dangers of medaling with what you dont understand - I made a very tasty 2.1 TSR golf engine go pop so will be approaching this very carefully and ensure I have enough info coming from my engine to know when things are not right.

 

So the specific question is what would a tuner use to remap a 993 ECU?

[Tim]

Megasquirters have taken an old ECU, cut the pcb away and used the plug as a wiring interface between the car wiring and the Megasquirt. This gives a plug compatible ecu with a swap out option if you want to use the car as std again !!

As for getting at the ECU data ??? I don't know ! It must be possible, but may be under expensive license agreement or something !!

[oliverjamesthomas]

So the specific question is what would a tuner use to remap a 993 ECU?

 

The same as they would for a 3.2 and most probably all other ECU equipped cars; an Emulator. The chip comes out, the emulator goes in and their computer becomes the chip. Once they've done, the file gets saved and is then transferred to a new chip that goes in the ECU.

 

Could you do it yourself? I'd say no. The laptop, the Emulator and the software can all be bought sure enough, but a rolling road would probably be good and then there's the knowledge. The software works on a hexadecimal basis and all there is on the screen for the most part is a grid of squares, each with a code such as (1A) or (16). Each block changes colour, (three colour choices generally) and that's as far as I can go with the software side.

 

What I would say is that there's plenty of scope for error. Changing one particular mapping point affects those around it and contrary to my previous belief that I'd be seeing loads of power runs, a lot of the work is done with the engine running at a given RPM level and just the aforementioned grid of squares. I'm sure someone will understand it, but to me it was just a whole new language. What is amazing though is the way changing one value a little results in the engine note changing a lot.

 

Wayne spent six hours on my 993 and only did five 'power runs' the whole time. Personally I'd just let him get on with it Jev, because the risk of bu**ering something up is just too great and the chances of achieving the optimum are fairly slim, IMHO. Oh, I went in with 273BHP, 261LBFT and the car stalling at low revs and drove away with 320BHP, 300LBFT and a very big smile!

[jevvy]

Thanks for filling in some gaps OJT, I have had a play with some emulators in the past and it all seems pretty logical. I also have a friend that does a lot of VAG tuning so I should have ok access to kit and software.

 

I hear what you say about "letting him get on with it" but that has not been my policy with this car, if I can do it myself I will especially if it can be cost effective to do so. I will at some point be inside the 3.6 and do some other bits and bobs to it so if I can install and understand DIY mapping between now and then I will be able to re-map and changes I make to the engine.

 

I also love the idea of the engine/car always dumping data to disc as its being driven then surely with careful research and tweaks to the maps I will be able to achieve a better running motor for all seasons and conditions rather then just shelling out for the best setup one August afternoon.

 

I will try to do some more reading and come back with some more specific questions.

[oliverjamesthomas]

Don't knock you one bit for trying to tackle everything yourself - good on you. Now, where's that welder; the one that welds rust.........?

[topcarrera]

Jevvy -

 

I am not an IT person but like you I have been thinking about the same thing and wondering what is involved/needed to effect a DIY re-map. Personally I agree with OJT that a WS re-map delivers a lot for £500 ish and I wouldn't like to practice on a 911 engine. I find the whole thing fascinating and would love to learn more about this. I guess there is a fair reason for the pros to keep details of their methods and kit to themselves but for a basic set-up like the ECU/Motronic on our cars it must be pretty straightforward ...........

 

Edit - Jevvy perhaps the control on your later engine is a bit more complex ...... Looking forward to IB.Com remap software in the near future!

Edited April 23, 2007 by topcarrera

[jevvy]

Andy

 

The way I see it is you can start gathering data as soon as you can hook things up, once thats in place then its a case of interpreting the stuff you have collected and see whats going on. I think that after 100's of miles driving you will have some obvious problems/weak points etc and its then a case of making tiny winy changes and then driving some more. This can all be done very slowly with very little risk to the engine if you are tight with your tweaks. The more you learn/tweak/gain the better it gets and the less risk there is.

 

As I understand it the knock sensor provides an early warning of detonation and you can measure the gasses to keep an eye on air/fuel so keeping an eye on these 2 and as long as you aren't an idiot and tune it to the moon on the fist change then it should all be good.

 

 

 

Road dyno:

http://www.roadtune.co.uk/roaddyno.shtml

[oliverjamesthomas]

Edit - Jevvy perhaps the control on your later engine is a bit more complex ...... Looking forward to IB.Com remap software in the near future!

 

The ECU's are very much the same in respect of the software and approach used to re-map them. One of the key elements though, appears to be having a map to use as a baseline. In my case, Wayne had a map from a Cup Car that he loaded to get the car running and see what was what. In Jake's case it was a 3.2 race car, IIRC. Because the computer and emulator replace the chip, without a map on the computer there isn't a map for the ECU to read. I should imagine that at some point someone has had a standard map loaded to their computer, but how you would do this I honestly don't know.

 

The other point to bear in mind is there's quite a lot to mapping that people don't initially think about. Many just think about AFR's in terms of the way an old carburettor works, but pulse width and frequency all come into play on the injector side of things, together with the resonances and reflections thereof that are passed down the exhaust. None of this is intended to scare people off and I don't wish to act the expert because I'm not; I'm just throwing it all out there for consideration.

[johndglynn]

Keep reading is my advice. I have been reading for months and am still learning lots. There are lots of aftermarket systems that can help home mappers, and your ECU is old tech so there must be an interface available. If not then as Tim says, sling the ECU and go to MS, use your old input as your MS connection, start with basic VE tables and work from there.

 

First thing I will do is go wideband afr, essential I think. You can hook up to a datalogger with 4 or 5 inputs for not much more money and then you are really going to start seeing value for money, record 40 minutes or so of data, come home, tweak this and that and go out again. Or buy dyno time and map it with an expert looking over your shoulder. Fit an afr gauge in the car and you can see if the mix is ever scary dangerous anywhere.

 

I totally agree home mapping is DIYable, there are thousands of guys out there at it now and I will be joining their ranks soon enough. Come up here for a few afternoons once we get started and we can learn it together - the dyno is just a short drive away.

[jevvy]

Excellent - loads of banter! Thanks for all the info, I will get my head in the books and report back.

 

In the mean time I have just spoken to a mate that does a lot of Vag tuning and he has all the kit and access to other stuff, he uses these guys:

 

http://race.dimsport.com/preparatori/chip....c6c〈=en

 

I have been mailing Wayne and he has gone AWOL - perhaps he has already hung up his dyno!

[Tim]

A low cost learning curve could involve a Digifant Mk2 Golf and a Megasquirt. The hardware is in place already and if it all goes wrong you could chuck it away

A lot cheaper than learning on a 911 motor

Tim

[oliverjamesthomas]

I have been mailing Wayne and he has gone AWOL - perhaps he has already hung up his dyno!

 

It's probably better to ring him. He's one of these blokes that like so many of us, works all hours. I understand he's been pretty busy with the start of the '07 motorsport season and people wanting cars tweaking to get that elusive few seconds but he was mapping a 993 belonging to a PCGB member, last week.

[strosek34]

Jevvy and JG,

 

Interesting thread this one, when you have both cracked it, put me down for 350HP please.

 

[topcarrera]

Jevvy and JG,

 

Interesting thread this one, when you have both cracked it, put me down for 350HP please.

 

 

Me too, what's it going to be "Jevtune" or "Glynnpower"

[oliverjamesthomas]

.... and if it goes south, I have a 204 bhp SC lump that's coming up for sale

[jevvy]

If I blow the 3.6 up then its a good excuse to crack it open - I say bring it on...!

[johndglynn]

.... and if it goes south, I have a 204 bhp SC lump that's coming up for sale

With all due respect to you both, the guy making his living from remapping might possibly be the wrong guy to talk to about DIY mapping. It doesn't sound to me like he explained much in plain english, as you seem to be saying he started talking about stuff you didn't fully understand, most of it went over your head but sounded pretty convincing, so you gave up on MS after one conversation.

 

Wayne and his fellow remappers (Chris at Weltmeister etc) have a massive amount of data concerning the intricacies of ultimate EFI performance, what works and what doesn't, but we are talking about getting it running and then tweaking things until it runs a bit better. The rule couldn't be simpler: watch your gases and temps, keep the afr safe and there is no difference to what the factory did.

 

There are a growing number of EFI guys on PP, and they are sharing good solid info, so no engines should get hurt. Having read what I have read in the last three months, I will be mucho surprised if from my setup I don't get:

• better starting and idling
  
• better throttle response
  
• better off-throttle response (zero mpg off throttle)
  
• better mpg on throttle
  
• better HP
  
• less WTF crap in the engine bay
  
• huge amounts more info coming out of the motor
  

and all for under a grand including wideband O2 and datalogging capabilities. That is the cost of two remaps. Then it will be crank-fired ignition and the redundant CIS stuff can go on eBay, making me some money back and giving me a more reliable car that runs better 100% of the time. Ultimate destination TPS/throttle bodies - yummy. Only downside (as George points out) is losing the classic CIS look in the short/medium term, which I kind of agree with, but then what's more attractive, K-Jet or intake stacks...

 

Instead of 'a bloke who probably understands this told me it was a bad idea', if anyone has any actual evidence of someone (preferably with a brain) who blew the shite out of their 911 engine by DIY EFIing/mapping it, then please point us towards it so we can ALL learn from it.

[jevvy]

but we are talking about getting it running and then tweaking things until it runs a bit better. The rule couldn't be simpler: watch your gases and temps, keep the afr safe and there is no difference to what the factory did.

 

and all for under a grand including wideband O2 and datalogging capabilities. That is the cost of two remaps.

 

Thats exactly where my brain is but I really want to try to make it happen with what I have rather then fitting after market kit - if Wayne etc can get the numbers with standard kit then I'm sure others could given enough time and a cautious approach.

 

Must admit, this does look like fun tho:

[Tim]

This is the classic carbs look JG, using Triumph TB's

Tim

[johndglynn]

This is the classic carbs look JG, using Triumph TB's

Go mate - is it back in the car yet?